1. Field of the Invention
The present invention relates to an input apparatus, a mobile apparatus, and an information recording medium, and in particular, relates to an input apparatus, a mobile apparatus, and an information recording medium that are well-suited to inputting in a small apparatus.
2. Description of the Related Art
Mobile communications terminals, such as mobile telephones, have the telephone function as the main function thereof, and thus, fundamentally, the input keys thereof are keys for a telephone. Additionally, in order to function as a telephone receiver, typically the housing as a whole is used in a lengthwise orientation. Additionally, from the perspective of ease of use of the keys, typically keys of a horizontal form factor are used.
On the other hand, given improvements in performance and functionality of mobile communications apparatus, there are those that are equipped with video imaging functions or television receiving functions, or equipped with functions that are compatible with higher information processing apparatus, such as personal computers (for example functions for executing business application software, functions for displaying web pages produced using personal computers, or the like). In mobile communications terminals, which are focused on the conventional telephone functions, there are no particular impediments to convenience even when using the display screen normally in the vertical orientation; however, because videos and screens for personal computers, and the like, have horizontal aspect ratios, display screens for portable telephones are often of a form that uses the horizontal orientation.
In consideration of this tendency, mobile communications terminals have been brought to market that can be used in both the vertical orientation and the horizontal orientation through, for example, innovations in the housing structure. For example, Unexamined Japanese Patent Application KOKAI Publication No. 2006-233998 discloses a structure that can be opened and closed in both the vertical orientation and the horizontal orientation in a foldable mobile communications terminal, wherein the mobile communications terminal can be used in either the vertical orientation or in the horizontal orientation depending on the application (a so-called “two-way style”).
However, because consideration has not been given to the key layout of the input keys, when used in the horizontal orientation there are problems with ease-of-use. That is, when the housing is used in the horizontal orientation with the conventional key form factor, the shape of each key will be vertical relative to the user, reducing the ease-of-use with fingertips. Additionally, the markings on the keys accommodate only the vertical orientation, so when used in the horizontal orientation, the keys are also difficult to read.
Furthermore, when functions that are compatible with personal computers, and the like, are provided, or when e-mail functions are used, etc., making it necessary to input text, text entry using the toggle method, which is unique to mobile communications terminals, is inefficient. As a result, there have been requests for the provision of keyboards that are equivalent to the full keyboards that are used in personal computers, and the like, but the provision of full keyboards in a small mobile communications terminal is difficult using the conventional key layout and key structure.